Lindum A/S is a leading Norwegian waste management company continuously looking for the most efficient and sustainable waste processing methods. Lindum is fully committed to circularity regarding waste collection and waste processing. The aim is to reuse all partial waste streams as much as possible. For example, biogas is produced when processing manure, digestion sludge and household waste. Lindum invests heavily in its search for new sustainable processing methods. The company is therefore justifiably proud of the pioneering role it plays in environmental matters.
Recovering heat from sludge
Incoming raw sludge is not sterile, therefore the first step is pasteurisation (hygienisation or sterilisation). Lindum A/S uses thermal pressure hydrolysis for this purpose. This technique heats the substrate by means of steam (high pressure). After the heating period, the temperature is quickly reduced to 40°C. This breaks the cell walls and fibres into small particles, which facilitates further degradation.
Sludge-water heat exchanger from Läckeby
Lars Erik Smith of construction company COWI contacted Lackeby in 2016. The task was to find a solution to use the existing process water as cooling water for the sludge. This way, the energy from this heated process water could be used back in the hydrolysis process. During the engineering phase, it became clear that the available process water was not as cool as expected and available building space was limited.
Lindum A/S, the client, had previous good experiences with Lackeby heat exchangers. Läckeby’s proposal therefore quickly led to an order. Using a Läckeby sludge-water heat exchanger ensures that this process is as efficient and cost-effective as possible.
